Exome
Sequence Analysis, DNA
High-Throughput Nucleotide Sequencing
Pedigree
Genome, Human
Mutation
Retinal Dystrophies
Mutation, Missense
Exons
Genetic Diseases, Inborn
Polymorphism, Single Nucleotide
DNA Copy Number Variations
A scalable, fully automated process for construction of sequence-ready human exome targeted capture libraries. (1/717)
(+info)Building a comprehensive genomic program for hepatocellular carcinoma. (2/717)
(+info)Rare, evolutionarily unlikely missense substitutions in CHEK2 contribute to breast cancer susceptibility: results from a breast cancer family registry case-control mutation-screening study. (3/717)
(+info)Exploring patterns and extent of bias in estimating divergence time from mitochondrial DNA sequence data in a particular lineage: a case study of salamanders (order Caudata). (4/717)
(+info)Diverging alternative splicing fingerprints in the transforming growth factor-beta signaling pathway identified in thoracic aortic aneurysms. (5/717)
(+info)Exome capture and massively parallel sequencing identifies a novel HPSE2 mutation in a Saudi Arabian child with Ochoa (urofacial) syndrome. (6/717)
(+info)Targeted sequencing of the human X chromosome exome. (7/717)
(+info)An atlas of tissue-specific conserved coexpression for functional annotation and disease gene prediction. (8/717)
(+info)The exome is the part of the genome that contains all the protein-coding regions. It represents less than 2% of the human genome but accounts for about 85% of disease-causing mutations. Exome sequencing, therefore, is a cost-effective and efficient method to identify genetic variants associated with various diseases, including cancer, neurological disorders, and inherited genetic conditions.
DNA Sequence Analysis is the systematic determination of the order of nucleotides in a DNA molecule. It is a critical component of modern molecular biology, genetics, and genetic engineering. The process involves determining the exact order of the four nucleotide bases - adenine (A), guanine (G), cytosine (C), and thymine (T) - in a DNA molecule or fragment. This information is used in various applications such as identifying gene mutations, studying evolutionary relationships, developing molecular markers for breeding, and diagnosing genetic diseases.
The process of DNA Sequence Analysis typically involves several steps, including DNA extraction, PCR amplification (if necessary), purification, sequencing reaction, and electrophoresis. The resulting data is then analyzed using specialized software to determine the exact sequence of nucleotides.
In recent years, high-throughput DNA sequencing technologies have revolutionized the field of genomics, enabling the rapid and cost-effective sequencing of entire genomes. This has led to an explosion of genomic data and new insights into the genetic basis of many diseases and traits.
High-throughput nucleotide sequencing, also known as next-generation sequencing (NGS), refers to a group of technologies that allow for the rapid and parallel determination of nucleotide sequences of DNA or RNA molecules. These techniques enable the sequencing of large numbers of DNA or RNA fragments simultaneously, resulting in the generation of vast amounts of sequence data in a single run.
High-throughput sequencing has revolutionized genomics research by allowing for the rapid and cost-effective sequencing of entire genomes, transcriptomes, and epigenomes. It has numerous applications in basic research, including genome assembly, gene expression analysis, variant detection, and methylation profiling, as well as in clinical settings, such as diagnosis of genetic diseases, identification of pathogens, and monitoring of cancer progression and treatment response.
Some common high-throughput sequencing platforms include Illumina (sequencing by synthesis), Ion Torrent (semiconductor sequencing), Pacific Biosciences (single molecule real-time sequencing), and Oxford Nanopore Technologies (nanopore sequencing). Each platform has its strengths and limitations, and the choice of technology depends on the specific research question and experimental design.
I must clarify that the term "pedigree" is not typically used in medical definitions. Instead, it is often employed in genetics and breeding, where it refers to the recorded ancestry of an individual or a family, tracing the inheritance of specific traits or diseases. In human genetics, a pedigree can help illustrate the pattern of genetic inheritance in families over multiple generations. However, it is not a medical term with a specific clinical definition.
A human genome is the complete set of genetic information contained within the 23 pairs of chromosomes found in the nucleus of most human cells. It includes all of the genes, which are segments of DNA that contain the instructions for making proteins, as well as non-coding regions of DNA that regulate gene expression and provide structural support to the chromosomes.
The human genome contains approximately 3 billion base pairs of DNA and is estimated to contain around 20,000-25,000 protein-coding genes. The sequencing of the human genome was completed in 2003 as part of the Human Genome Project, which has had a profound impact on our understanding of human biology, disease, and evolution.
A mutation is a permanent change in the DNA sequence of an organism's genome. Mutations can occur spontaneously or be caused by environmental factors such as exposure to radiation, chemicals, or viruses. They may have various effects on the organism, ranging from benign to harmful, depending on where they occur and whether they alter the function of essential proteins. In some cases, mutations can increase an individual's susceptibility to certain diseases or disorders, while in others, they may confer a survival advantage. Mutations are the driving force behind evolution, as they introduce new genetic variability into populations, which can then be acted upon by natural selection.
Retinal dystrophies are a group of genetic eye disorders that primarily affect the retina, a light-sensitive layer at the back of the eye. These conditions are characterized by progressive degeneration and death of photoreceptor cells (rods and cones) in the retina, leading to vision loss.
The term "dystrophy" refers to a condition that results from the abnormal or defective development and function of tissues or organs. In the case of retinal dystrophies, the photoreceptor cells do not develop or function properly, resulting in visual impairment.
Retinal dystrophies can present at any age, from infancy to adulthood, and can have varying degrees of severity. Some common symptoms include night blindness, decreased visual acuity, loss of peripheral vision, light sensitivity, and color vision abnormalities.
Examples of retinal dystrophies include retinitis pigmentosa, Stargardt disease, Usher syndrome, and Leber congenital amaurosis, among others. These conditions are typically inherited and can be caused by mutations in various genes that play a role in the development and function of the retina.
There is currently no cure for retinal dystrophies, but research is ongoing to develop treatments that may slow or halt the progression of these conditions, such as gene therapy and stem cell transplantation.
A missense mutation is a type of point mutation in which a single nucleotide change results in the substitution of a different amino acid in the protein that is encoded by the affected gene. This occurs when the altered codon (a sequence of three nucleotides that corresponds to a specific amino acid) specifies a different amino acid than the original one. The function and/or stability of the resulting protein may be affected, depending on the type and location of the missense mutation. Missense mutations can have various effects, ranging from benign to severe, depending on the importance of the changed amino acid for the protein's structure or function.
Exons are the coding regions of DNA that remain in the mature, processed mRNA after the removal of non-coding intronic sequences during RNA splicing. These exons contain the information necessary to encode proteins, as they specify the sequence of amino acids within a polypeptide chain. The arrangement and order of exons can vary between different genes and even between different versions of the same gene (alternative splicing), allowing for the generation of multiple protein isoforms from a single gene. This complexity in exon structure and usage significantly contributes to the diversity and functionality of the proteome.
Inborn genetic diseases, also known as inherited genetic disorders, are conditions caused by abnormalities in an individual's DNA that are present at conception. These abnormalities can include mutations, deletions, or rearrangements of genes or chromosomes. In many cases, these genetic changes are inherited from one or both parents and may be passed down through families.
Inborn genetic diseases can affect any part of the body and can cause a wide range of symptoms, which can vary in severity depending on the specific disorder. Some genetic disorders are caused by mutations in a single gene, while others are caused by changes in multiple genes or chromosomes. In some cases, environmental factors may also contribute to the development of these conditions.
Examples of inborn genetic diseases include cystic fibrosis, sickle cell anemia, Huntington's disease, Duchenne muscular dystrophy, and Down syndrome. These conditions can have significant impacts on an individual's health and quality of life, and many require ongoing medical management and treatment. In some cases, genetic counseling and testing may be recommended for individuals with a family history of a particular genetic disorder to help them make informed decisions about their reproductive options.
Single Nucleotide Polymorphism (SNP) is a type of genetic variation that occurs when a single nucleotide (A, T, C, or G) in the DNA sequence is altered. This alteration must occur in at least 1% of the population to be considered a SNP. These variations can help explain why some people are more susceptible to certain diseases than others and can also influence how an individual responds to certain medications. SNPs can serve as biological markers, helping scientists locate genes that are associated with disease. They can also provide information about an individual's ancestry and ethnic background.
DNA Copy Number Variations (CNVs) refer to deletions or duplications of sections of the DNA molecule that are larger than 1 kilobase (kb). These variations result in gains or losses of genetic material, leading to changes in the number of copies of a particular gene or genes. CNVs can affect the expression level of genes and have been associated with various genetic disorders, complex diseases, and phenotypic differences among individuals. They are typically detected through techniques such as array comparative genomic hybridization (aCGH), single nucleotide polymorphism (SNP) arrays, or next-generation sequencing (NGS).
A homozygote is an individual who has inherited the same allele (version of a gene) from both parents and therefore possesses two identical copies of that allele at a specific genetic locus. This can result in either having two dominant alleles (homozygous dominant) or two recessive alleles (homozygous recessive). In contrast, a heterozygote has inherited different alleles from each parent for a particular gene.
The term "homozygote" is used in genetics to describe the genetic makeup of an individual at a specific locus on their chromosomes. Homozygosity can play a significant role in determining an individual's phenotype (observable traits), as having two identical alleles can strengthen the expression of certain characteristics compared to having just one dominant and one recessive allele.